Device for decreasing yarn tension



Aug. 10, 1965 Filed April 10, 1963 R. JENNY DEVICE FOR DECREASING YARN TENSION 2 Sheets-Sheet l INVENTOR Aug. 10, 1965 R. JENNY 3,199,806

DEVICE FOR DECREASING YARN TENSION Filed A ril 10, 1963 2 Sheets-Sheet 2 1 INVENTOR 9 4 BY Rudolf TEA/N] ZTWLJ m United States Patent M 3,1993% DEVICE FGR DECREASING YARN TENSIQN Rudolf Jenny, Thalwil, Switzerland, assignor to Maschinenfabrik Schweiter AG., Horgen, Switzerland, a corporation of Switzerland Filed Apr. 10, 1963, Ser. No. 271,913 Claims priority, application Switzerland, Apr. 16, E52, 4,348/ 62 11 Claims. (Cl. 242--128) The present invention relates to an improved device for the reduction of thread or yarn tension during withdrawal or unwinding of the thread or yarn over the head or top end of a spool or cop, particularly adapted for use in conjunction with textile machinery.

A number of different devices have already become known to the art which attempt to solve the problem of withdrawing or unreeling the yarn at great speeds, as such occurs in winding machines for example. When working with high speed yarn pay-o or withdrawal, as is known, a balloon is formed at the unwound thread or yarn between a guide member and the cop or spool which causes a considerable increase in tension at the yarn. The formation of balloons especially occurs with small to medium withdrawal or unwinding distances, that is to say, at that location where during the entire yarn withdrawal or unwinding operation only a single balloon is formed, or where the danger exists that the multiple balloon which forms at the beginning of the yarn unwinding or withdrawal operation forms into a single balloon during such yarn unwinding. Particularly with the last-mentioned situation where there is a conversion of a multiple balloon into a single balloon, there occurs a pronounced increase in tension which can directly lead to yarn breakage. Furthermore, there exists the danger that loops are formed in the region of the spool which likewise limit the unwinding speed of the yarn and/or at high unwinding speeds lead to yarn breakage.

The heretofore known devices for influencing yarn tension all possess disturbance members which either constrict or bind-up the single balloon which is forming, or

break or collapse such that a number of balloons are formed. It has been shown, however, that the majority of these devices are not capable of maintaining the withdrawal of the yarn from a spool or cop in the form of a multiple balloon throughout the ent re duration of the yarn unreeling operation, primarily for the reason that, there has not been sufliciently taken into consideration the influence of the increase in the unwinding or withdrawal distance with progressing emptying of the cop or spool.

The present invention proceeds from the recognition that the breaking point of the yarn balloon, that is, that location of the thread or yarn at which a contact or impact therewith must take place in order to permit formation of a multiple balloon, travels or changes its position during the yarn pay-01f or unwinding operation. Furthermore, in accordance with the teachings of the present invention there is also endeavored to construct the shape of the yarn disturbance or impact member such that the guiding of the yarn into the same is readily possible, which is of particular importance in conjunction with its application at automatic winding machines.

A further noteworthy characteristic of the present invention resides in the recognition that the impact or engagement of the disturbance member with the balloon is then most effective when such occurs as close as possible to a stationary yarn guide member, and, indeed for the reason that, the effect of this disturbance member is then transmitted back over the entire unwound or payedott length of the yarn to the point of pay-oft at the cop 3,19%,896 Patented Aug. 10, 1&6?

or spool, thereby considerably preventing formation of loops.

The inventive process for the diminution of yarn tension is generally manifested in the feature that the disturbance member is brought into operation in the region of the balloon belly which lies closest to a yarn guide member, and its eifect is maintained throughout the entire region of the change of the yarn unwinding or withdrawal length during pay-off of yarn from the cop or spool. More specifically, the inventive method of reducing yarn tension in a yarn which travels from a cop from which it is wound to a yarn infeed location and tends to form at least one yarn balloon comprises the steps of applying an impact force to the belly of the yarn balloon closest to said yarn infeed location, setting up a force through such impact in said yarn which travels from the point of impact back to the wind-0E location of the yarn from the cop, to thereby either break-up said yarn balloon into a number of yarn balloons if only one such yarn balloon is initially present, and if a number of yarn balloons were initially present said impact force prevents such number of yarn balloons from forming a single yarn balloon.

Additionally, the present invention relates to an improved apparatus or device for reducing yarn tension which is manifested by the fact that, the disturbance means exhibit two disturbance or impact surfaces preferably arranged at right angles or substantially right angles to one another, wherein their vertical line of intersection or apex is located along the yarn axis, whereby its extension in this direction as well as its position between a pay-olf spool or cop and a yarn guide member is so selected that in spite of changes in the yarn withdrawal length during unwinding of the yarn a multiple balloon is maintained. In a variant constructional form of the disturbance member such is provided with slotted portions adapted to receive yarn feeling fingers of a yarn feeler mechanism provided for sensing the presence of yarn between a supply cop and yarn infeed location, the latter of which is generally constructed in the form of a suitable yarn guide member.

Accordingly, it is a primary object of the present invention to provide an improved method and device for reducing yarn tension, particularly with high speed unreeling of cops in textilemachinery.

A further important object of the present invention is to provide an improved method of unwinding yarn or thread from a cop or spool with reduced yarn tension, wherein a yarn balloon is subject to an impact force at its balloon belly at a predetermined location to collapse such balloon into a number of balloons, or if a number of yarn balloons are already present such impact force ensures against formation of a single yarn balloon.

Another important object of the present invention is the provision of an improved disturbance member provided with yarn impact surfaces, which disturbance member is constructed and arranged in such a manner that it automatically takes into consideration changes in the yarn withdrawal length from a supply cop and a yarn infeed location, these changes being due to progressive unwind ing of the yarn from its cop.

Still another important object of the present invention is to provide an improved disturbance member adapted to impace the belly of a yarn balloon as it travels from a cop to a yarn infeed location, the latter of which is generally defined by a yarn guide organ, with the point of impact of said disturbance member with the yarn advantageously undertaken at the balloon belly closest to said yarn infeed location, and with said disturbance member being so configured and arranged that proper yarn impact is ensured in spite of changes in length between the point of yarn pay-off from the cop and the aforesaid yarn infeed location.

from the detailed description given hereinafter; it should be understood, however, that the detailed description and specific examples, while indicating preferred embodiments of the invention, are given by way of illustration only, since various changes and modifications within the spirit and scope of the invention will become apparent to those skilled in the art from this detailed description.

In the drawings:

FIGURE 1 is a perspective view of a device for reduc ing yarn tension according to the present invention arranged at a winding machine and depicting the yarn unwinding or withdrawal path;

FIGURE 2 is a perspective view illustrating a second embodiment of the inventive device provided for an automatic Winding machine;

FIGURE 3 is a plan view of the device illustrated in FIGURE 2 showing details thereof; and

FIGURE 4 is an end view of the disturbance member depicted in FIGURE 1 showing details thereof;

Referring now to the drawings and, more specifically to FIGURE 1, wherein only enough of a textile machine is illustrated to enable one to understand the teachings of the invention, it will be seen that reference numeral 1 denotes a spool or cop which carries upon its sleeve body a cop winding or yarn or thread package 2. The cop 1 is seated on a cop holder or the like of a winding machine, in a manner not shown in further detail but readily known to the art. The axis A of the cop 1 is directed in known manner towards what has been generally termed herein as a yarn infeed location 3, which advantageously is either in the form of a guide member, brake member, or cleaning member, and through which the yarn or thread F unwound from the aforesaid cop 1 passes on its way to the winding spool.

Between the cop 1 and the yarn infeed location 3 there is advantageously arranged disturbance'means 4 preferably in the form of an angle section or plate 4a. The inner surfaces 5 and 6 of the angle plate 411 terminate in abutting confronting reiation at a line of intersection or apex 7 and together enclose generally a right angle, with the diverging ends of this angle plate providing a relatively large opening facilitating entry of the yarn into the disturbance means 4. Moreover, at these surfaces 5, 6 of the angle member 4a there can advantageously be provided peaks and valleys in the form of ribs or projections 8 and depressions or grooves 9 which extend in the axial direction of said angle member (see FIGURE 4), and which preferably run into one another in undulated or wave-like fashion. As previously mentioned, these internal surfaces 5 and 6 of the disturbance means 4 converge in confronting relation along a vertical line 7 dissposed along the yarn axis and the axis A of the cop 1.

In addition to the above-mentioned instruction or condition as regards the position of the vertical line of intersection or apex 7 of the impact surfaces 5 and 6 of the disturbance means 4 for the herein-after to be described operation of said disturbance means,.its length and position between the cop 1 and the yarn infeed location 3 have also been found to be of importance. It will be appreciated that as the yarn or thread F is unwound from the cop 1 and travels in the direction of the yarn infeed location 3 it moves through a substantially helical or spiral path and tends to build one or more yarn balloons B.

As-can best be seen by inspecting FIGURE 1, the disturbance means 4 is situated relatively close to the yarn infeed location 3, here depicted as a guide member, that is, the distance a between the upper edge 4b of such disturbance means 4 and the yarn infeed location 3 is relatively small. In relation to this distance a, the disturbance means or device 4 possesses a relatively'large length l in the direction of the axis A of the cop 1 which is a multiple of such distance a. The length l of the disturbance means 4 is advantageously so chosen that in spite of changes in the yarn or thread balloon B during unwinding of the yarn F from the cop 1 a balloon belly is always subject to an impact or disturbance force, that is, this balloon bell generally designated by reference numeral C abuts against one of the internal impact surfaces 5 or 6 of the disturbance means 4.

Due to contact of the uppermost balloon belly C with the disturbance device or means 4, the oscillation produced in the yarn travels back to the cop 1 opposite to the direction of yarn travel. This results in a facilitation of the unreeling of the yarn F from the cop 1, considerably prevents a binding or constriction of the thread or yarn F at the upper end of the cop 1, and thereby also considerably prevents braking of such yarn. If during the yarn unwinding operation there is formed a single balloon B or if there exists a tendency to form such a sin le balloon, then a balloon breaking or collapsing effect results due to contact of its balloon belly C with the impact surfaces 5, 6 of the disturbance means 4 so that the yarn F is transformed into a multiple balloon.

In a practical application of the device, it has been found that with a yarn unwinding or withdrawal distance L, that is, with a distance between the lower end of the cop 1 and the yarn infeed location 3 equal to 550 millimeters and a length of 280 millimeters of the cop sleeve, it is advantageous to have the distance a of the disturbance means 4 from the yarn infeed location 3 equal 20 millimeters, with a length l of the disturbance means 4 equal to millimeters. Upon changing the sleeve length of the cop 1 the length l of the disturbance means 4 can also be correspondingly changed. However, it has been found that with practically all yarn withdrawal or unwinding distances L which come into practical consideration, a length of 90 millimeters for the disturbance means 4 is advantageous and, only an increase above this value under specific circumstances can still bring specific advantages. According to the length l of the disturbance means 4, it is also possible to change the distance a to the yarn infeed location 3. This distance a will generally most always lies between 15 and 25 millimeters. A yarn withdrawal or unwinding distance of 550 millimeters between the lower end of the cop 1 and the yarn infeed location 3 substantially corresponds to a distance which is approximately present in automa tic winding machines for example. It will be appreciated that the yarn withdrawal distance, which is the distance between the point the yarn leaves the cop 1 and the yarn infeed location 3 continually changes as the yarn unwinding operation proceeds, and in the end condition that is when the yarn package on the cop 1 is exhausted such yarn Withdrawal distance then corresponds to the value L. It should further to appreciated that since this yarn withdrawal distance continually changes during yarn unreeling, the spatial position of the yarn balloon or balloons likewise tends to change. However, since the impact surfaces 5 and 6 of the yarn disturbance means 4 extend over a considerable portion of the aforesaid yarn withdrawal distance and, as such, provide extended impact surfaces, there is ensured that an impact force will always be applied to the belly C of the uppermost yarn balloon, even if the latter tends to shift somewhat during yarn unwinding.

Referring now to the embodiment illustrated in FIG- URES 2 and 3 wherein like reference numerals generally designate similar elements, it will be recognized that such illustrates an accommodation or adaptation of the disturbance means 4 for the purpose of yarn or thread deection at an automatic cross-winding machine. The disturbance means 4 likewise constructed as an angle plate or section 4a, is provided above its two legs or side pieces 40 with suitably configured slots or recesses 10. These slots extend in transverse direction to the apex or lengthwise axis of the angle plate 411 and through which there can move a three-fingered feeler member 12 pivotably or rockably mounted at a sleeve or boss 11. The feeler member 12 includes a lever arm member 13 through the agency of which said feeler member is operatively associated with a doublearm lever 14 provided with the arms 14a and 14b. The double-arm lever 14 is in turn actuatable from a drive or push rod 15 which carries a pin 15a engageable with a slot 14c of the arm 14b.

The drive or push rod 15 which is automatically pushed forward in the direction of the arrow D by a suitable feeler mechanism of the winding machine upon the presence of yarn breakage between a yarn brake and the wind-up spool, cooperates with the switching-arm 16 of a limit switch 17 or suitable expedient. If the push or drive rod 15 is displaced forwardly in the direction of the arrow D then the latter rocks the yarn feeler 12, via the double-arm lever 14 and the arm member 13, out of the position shown in full-lines in FIGURE 3 in counter-clockwise direction into the position denoted by reference numeral 12a. If the yarn F is situated in the region of the vertical line 7 defined by the intersection of the two impact surfaces 5, 6 of the disturbance means 4, then the feeler 12 remains in its corresponding position. On the other hand, if a yarn F is no longer present between the cop sleeve 1 and the yarn infeed location 3 or if the yarn does not properly pass through the disturbance means 4, then the yarn feeler 12 can pivotably move in counter-clockwise direction through the slots 19 of the disturbance means 4 into the endposition illustrated in phantom lines by reference numeral 1%. Such, on the other hand, permits a movement of the push-rod 15 into its extreme position represented by numeral 15b in FIGURE 3, in which it undertakes via the switching arm 16 an actuation of the limit switch 17, and by means of which the automatic change mechanism of the winding machine is started into op eration in order to remove the cop 1 which is considered to be exhausted and to replace such with a full cop. Moreover, the inner disturbance or impact surfaces 5 and 6 of the disturbance means 4 can, in a manner similar to the embodiment of FIGURES l and 4, be provided with longitudinally extending peaks and valleys in the form of ribs and depressions such as depicted in FIGURE 4, which however in this case will be interrupted by the slots 10. Such ribs of wave-like configuration have the function, as in the embodiment of FIGURE 1, to place the yarn F withdrawn past the disturbance or impact surfaces 5 and 6 into an intensive oscillation, and thereby to increase the number of yarn balloons or to maintain the unwound yarn in the form of a multiple balloon.

While there is shown and described present preferred stood that the invention is not limited thereto but may be otherwise variously embodied and practised within the scope of the following claims.

Having thus described the present invention, what is desired to be secured by United States Letters Patent is:

1. Device for decreasing yarn tension during unwinding of yarn from a cop, which yarn is moving from the cop through a predetermined path of travel towards a yarn infeed location, comprising disturbance means for yarn balloons disposed in said path of travel between said cop and said yarn infeed location, said disturbance means consisting of only one pair of impact surfaces located at substantial-1y right angles to one another, said impact surfaces meeting along a line of intersection substantially situated along the yarn axis and axis of the cop, the position of said impact surfaces between said cop and yarn infeed location as well as the length of said impact surfaces extending in the direction of said cop axis being so '6 selected that in spite of changes in the yarn withdrawal length between the point of yarn outfeed from the cop and the yarn infeed location during unwinding of the yarn from the cop a multiple yarn balloon is maintained.

2. Device as defined in claim 1; wherein said disturbance means are disposed in the region of said yarn infeed location, the length of said impact surfaces of said distunbance means being a multiple of the spacing between said disturbance means and said yarn infeed location.

3. Device as defined in claim 1; wherein said impact surfaces are defined by an angle section.

'4. Device as defined in claim 2; wherein with a spacing of the lower end of the cop from the yarn infeed location at approximately 500 millimeters and with a spacing of the disturbance means from the yarn infeed location at approximately 20 millimeters, the length of said impact surfaces extending in the direction of the cop axis is at least millimeters.

5. Device for decreasing yarn tension during unwinding of yarn from a cop moving through a predetermined yarn path of travel towards a yarn guide member, comprising disturbance means for yarn balloons disposed in said path of travel between said cop and said yarn guide member, said disturbance means consisting of only a pair of impact surfaces located at substantially right angles to one another, said impact surfaces meeting along a substantially vertical line of intersection disposed along the yarn axis and the axis of the cop, the position of said impact surfaces between said cop and yarn guide member as well as the length of said impact surfaces extending in the direction of said cop axis being so selected that in spite of changes in the yarn withdrawal length between the point of yarn outfeed from the cop and the yarn guide member during unwinding of the yarn from the cop a multiple yarn balloon is maintained.

6. The combination wit-h a cop carrying a yarn package from which yarn is unwound and travels to a yarn infeed location, of means for reducing yarn tension, said means comprising a disturbance member disposed in the path of yarn travel between said cop and yarn infeed location, said disturbance member consisting of only a pair of impact surfaces located at substantially right angles to one another, said impact surfaces converging along a line of intersection positioned along the yarn axis and the axis of the cop, with the diverging ends of said pair of impact surfaces located remote from said line of intersection defining a relatively large opening facilitating entry of the yarn between said pair of impact surfaces, the position of said impact surfaces between said cop and yarn infeed location as well as the length of said impact surfaces extending in the direction of said cop axis being so selected that in spite of changes in the yarn withdrawal length between the point of yarn outfeed from the cop and the yarn infeed location during unwinding of the yarn from the cop said impact surfaces contact the balloon belly of a yarn balloon disposed closest to said yarn infeed location.

7. A disturbance member for yarn balloons consisting of an angle plate providing only a pair of converging impact surfaces meeting along a line of intersection extendding between opposite ends of said impact surfaces, said impact surfaces enclosing substantially a right angle therebetween.

8. Device for decreasing yarn tension during unwinding of yarn from a cop, which yarn is moving from the cop through a predetermined path of travel towards a yarn infeed location, comprising disturbance means for yarn balloons disposed in said path of travel between said cop and said yarn infeed location, said disturbance means comprising an angle section incorporating a pair of impact surfaces located at substantially right angles to one another, said impact surfaces being provided with a plurality of ribs and intermediate grooves extending in the axial direction of said disturbance means, said impact surfaces meeting along a line of intersection situated along the yarn axis and the axis of the cop, the position of said impact surfaces between said cop and yarn infeed location as well as the length of said impact surfaces extending in the direction of said cop axis being so selected that in spite of changes in the yarn withdrawal length between the point of yarn outfeed from the cop and the yarn infeed location during unwinding of the yarn from the cop a multiple yarn balloon is maintained.

9. Device for decreasing yarn tension during unwinding of yarn from a cop, which yarn is moving from the cop through a predetermined path of travel towards a yarn infeed location, comprising disturbance means for yarn balloons disposed in said path of travel between said cop and said yarn infeed location, said disturbance means including a pair of impact surfaces located at substantially right angles to one another, said impact surfaces meeting along a line of intersection situated along the yarn axis and the axis of the cop, said impact surface of said disturbance means being provided with at least one transversely extending, elongated opening defining a slot in the region of said line of intersection, feeler means mounted for movement into a yarn detecting position disposed to cooperate with said slot, means for displacing said feeler means into said slot into its yarn detecting position in response to a given operating condition present at a textile machine, the position of said impact surfaces between said cop and yarn infeed location as well as the length of said impact surfaces extending in the direction of said cop axis being so selected that in spite of changes in the yarn withdrawal length between the point of yarn outfeed from the cop and the yarn infeed location during unwinding .of the yarn from the cop a multiple yarn balloon is maintained.

it). A disturbance member for yarn balloons consisting of an angle plate providing a pair of converging impact surfaces meeting along a line of intersection extending between opposite ends of said impact surfaces, said impact surfaces enclosing substantially a right angle therebetween, said impact surfaces being provided with a plurality of projections and intermediate grooves which extend lengthwise of said impact surfaces.

11. A disturbance member for yarn balloons consisting of an angle plate providing a pair of converging impact surfaces meeting along a line of intersection extending between opposite ends of said impact surfaces, said impact surfaces enclosing substantially a right angle therebetween, said impact surfaces being provided with an elongated opening defining at least one slot member extending transversely thereof in the direction of said line of intersection and adapted to receive a yarn feeler member.

References Cited by the Examiner UNITED STATES PATENTS 2,825,214 3/58 Pernick 66163 2,994,491 8/61 Weber 242-128 3,011,736 12/61 Furst et al. 242-128 M'ERVIN STEIN, Primary Examiner. 

1. DEVICE FOR DECREASING YARN TENSION DURING UNWINDING OF YARN FROM A COP, WHICH YARN IS MOVING FROM THE COP THROUGH A PREDETERMINED PATH OF TRAVEL TOWARDS A YARN INFEED LOCATION, COMPRISING DITURBANCES MEANS FOR YARN BALLOONS DISPOSED IN SAID PATH OF TRAVEL BETWEEN SAID COP AND SAID YARN INFEED LOCATION, SAID DISTURBANCE MEANS CONSISTING OF ONLY ONE PAIR OF IMPACT SURFACES LOCATED AT SUBSTANTIALLY RIGHT ANGLES TO ONE ANOTHER, SAID IMPACT SURFACES MEETING ALONG A LINE OF INTERSECTION SUBSTANTIALLY SITUATED ALONG THE YARN AXIS AND AXIS OF THE COP, THE POSI- 